Lubricating system for rock drills



Oct. l, 1946. o. J. SCHORER LUBRICATING SYSTEM FOR ROCK DRILLS Filed July :51, '1945 Patented Oct. 1, 1946 Y 2,408,534 LBRICATING srs'rEr/r Fon Rooi; DRILLs Otto J. Schorer, Holyoke, Mass., assigner to Worthington Pump and Machinery Corporation, Harrison, N. J., a corporation of Dela- Wavre Application July 31, 1945, Serial N0. 607,941 I l A Y This invention relates Vto percussive tools and 'more particularly to an oiling or lubricating struc'- ture for pressure fluid actuated rock drills.

An--obiect of the present invention is to provide a lubricating system for rock drills or the like, which will supply the necessary lubricating oil to the various working parts of the drill, uti' With these and otherr objects in view as may' appear from the accompanying specification, the

invention consists of various features of construction and combination of parts, which will be first described in connection with the accompanying drawing showing a longitudinal section through a rock drill constructed in accordance with the invention, and the features forming the invention will |be specifically pointed out in the claims.

Referring more particularly to the drawing, the rock drill of the hammer piston type may be of any approved form and comprises the cylinder I in which the piston 2 is reciprocated by means of air or other suitable fluid under pressure.

The pressure fluid enters the rock drill through the throttle valve 3 and passes into the annular distributing channel 4 from where it passes through suitable ports and passages under control of the control valve 5 into the cylinder I for reciprocating the piston 2 in the usual manner of operation of rock drills and other percussive tools of this type. A lubricant chamber 5 is formed in the wall of the cylinder I and has a filling opening in one end which is normally closed by the plug l. An orice plate 8 is located in the reservoir 6 a suitable distancev inwardly from the inner end of the plug 1 and has a restricting orifice 9 therein. The space between the orifice plate 8 and the inner end of the plug 1 is filled with felt or other absorbent material.

An opening or passageway IQ establishes communication between the felt-containing chamber II, which is the space in the reservoir 6 between the orifice plate 8 and the plug l, and the passage l2 formed in the cylinder I. The passage I2 has communication with the annular distributing channel 4 and with the chamber in which the control valve 5 operates.

The cylinder front head I3 has an annular oil chamber I4 formed therein, and this chamber I4 has communication through an opening I5 with theV oil reservoir 6. One or more grooves I'l are c ut in the perimeter ofthe flange I8 Aforrned on the rear end of the cylinder vfront head I3,and it' or lthey establish communication passages through which lubricant may pass from the chamber I4 into the cylinder I forwardly of the head I9 of the piston 2.

In operation; pressure air is admitted, `when the throttle valve 3 is open, into the channel 4, and passes through the passageways I2 and I@ into the felt-containing chamber I I, and through the orifice 9, chamber 6, and opening I5 into the oil chamber I4. This pressure air forces a small amount of oil in vapor form through the groove or grooves Il into the cylinder where it contacts the surfaces of the reciprocating piston 2. This ow of oil or lubricant takes place during the return or rearward movement of the piston 2, Some of the oil or lubricant which is distributed to the piston 2 through the groove or grooves I1 passes forwardly along the piston 2 during successive operation, and works its way into the chuck structure 20 to provide proper lubrication thereof.

When the piston is making its forward stroke, and as it approaches its cushioning position, as shown in the drawing, it builds up a pressure forwardly of the piston head I9 in excess of the pressure through the passages Il) and 4 (owing to a pressure drop caused in these passages by the action of the valve 5) and pressure air together with oil vapor is forced through the opening I5 into the chamber 6 through the orifice 9, felt chamber II, passages In and I2 into the chamber in which the valve 5 operates, thus lubricating the valve. At this time oil vapor is also carried or forced into the cylinder I rearwardly of the piston head I9 where the oil vapor lubricates the cylinder walls, the rie bar 2I and all other moving parts of the drill in the rearward part thereof.

It will be understood that the invention is not to .be limited to the specific construction or arrangement of parts shown, but that these may be widely modied within the invention as defined by the claims.

What is claimed is:

1. In a lubricating device for rock drill the combination of a cylinder, a piston reciprocable therein and having a head, a valve chamber in the rear end of said cylinder, a iront head for the cylinder, said cylinder provided with ports and passages for the distribution of pressure air, said cylinder provided with an oil chamber, said front head having an oil chamber therein, a passage in the cylinder establishing communication between the oil chamber in the cylinder and the oil chamber in said front head, said front head having a passageway .cut therein opening from its contained oil chamber into the cylinder in front of the forward end of the piston head, and said cylinder having a passageway therein establishing communication between the cylinder contained oil chamber and one of said cylinder contained pressure air passageways. Y

2. In a lubricating device for rock drills Ythe combination of a cylinder, a piston recprocable therein and having a head, a valve chamber, in the rear end of said cylinder, a front head'for the cylinder, said cylinder provided with ports and passages for the distribution of pressure air, said cylinder provided with an oil chamber, said front head having an oil chamber therein, a passage in the cylinder establishing communication between the o-il chamber in the cylinder and the oil chamber in said front head, said front head having a passageway cut therein opening from its contained oil chamber into the cylinder in front of the forward end of the piston head, and said cylinder having a passageway therein establishing communication between the cylinder contained oil chamber and one of said cylinder contained pressure air passageways, and an orice plate having a restricting orifice therein in said cylinder contained oil chamber.

4 3. In a lubricating device for rock drills the combination of a cylinder, a. piston reciprocable therein and having a head, a valve chamber in the rear end of said cylinder, a front head for the cylinder, said cylinder provided with ports and passages for the distribution of pressure air, said cylinder provided with an oil chamber, said front head having an oil chamber therein, a passage in the cylinder establishing communication between the oil chamber in the cylinder and the oil chamber in said front head, said front head having a passageway cut therein opening from its contained oil chamber into the cylinder in front of the forward end of the piston head, and said cylinder having a passageway therein establishing communication between the cylinder contained oil chamber and one of said cylinder contained pressure air passageways, and an orifice plate having a restricting orifice therein in said cylinder contained oil chamber, said orice plate forming a chamber in one end of the oil chamber, absorbent material in said chamber formed by said orifice plate, said passageway which establishes .communication between said cylinder contained oil chamber and one of said cylinder contained air passageways opening into the chamber for-med by said orifice plate.

OTTO J. SCHORER. 

